Florida71 wrote: "To each his/her own, but a pair of 12” drivers shouldn’t need a subwoofer."
There is a tradeoff relationship between low-end extension, box size, and efficiency. A high efficiency woofer, regardless of its diameter, has to trade off low-end extension in order to get that high efficiency. Along the way, the lighter cone and powerful magnet make the high efficiency woofer pretty articulate higher up the spectrum. I don’t know the particulars of the woofer in the Heresy, but it probably has a motor-strength-to-moving-mass ratio that compares favorably with cute little audiophile midwoofers.
And here’s how box size fits in: In order to have another octave of low-end extension and maintain the same efficiency, the Heresy would need a box EIGHT TIMES the size. This is assuming a such a woofer exists, and to the best of my knowledge it doesn’t. Much cheaper and more practical to add subs.
One may or may not agree with the tradeoffs Klipsh chose for the Heresy, but imo they did a competent juggling of those tradeoffs.
Duke